The goal of this proposal is to participate as a clinical site in a nation-wide study of neuroprotection in Parkinson's disease (PD). There are several reasons to believe that such a trial is warranted. First, a number of compounds and therapeutic strategies now exist that may modify the progression of PD. Second, previous trials have offered lessons in study design that may now be incorporated into neuroprotection trials. The combination of the availability of promising compounds and the evolution of clinical trials methodology to study PD progression make the present an ideal time to initiate further study of neuroprotection in PD. As a clinical site, our primary objective will be to recruit and retain research subjects to participate in the proposed clinical trial. We plan to recruit at least 2 patients per month (12 total) during the recruitment phase of the pilot studies and 2 patients per month during the main trial (72 patients). The University of Pennsylvania Parkinson's Disease and Movement Disorders Center (PDMDC) has a staff of highly qualified clinical investigators and extensive experience in the design and conduct of single- and multi-center clinical trials in PD. The center has a track record of successful recruitment and retention of research participants at all stages of PD. We propose to partner with the recently funded Parkinson's Disease Research, Education and Clinical Center (PADRECC) to enhance enrollment. We recognize that the clinical centers may have responsibilities in addition to recruiting patients. These responsibilities will include: collaboration with other clinical centers and with the coordinating center and biostatistical center, participation in the cooperative design of the study protocols and operations manuals, cooperation with data audits and study monitors, agreement to publish data collected at our site only in accordance with the guidelines established by the study publications committee, to take all appropriate measures to protect human subjects and to ensure adequate representation of genders and racial and ethnic minorities. The PDMDC is also prepared to participate in these responsibilities.